binary pattern match performance

bin_element.erl

-module(bin_element).

-export([run/1]).

-define(CHUNK_SIZE, 1049).

run(Chunks) ->
    BinL = [crypto:strong_rand_bytes(?CHUNK_SIZE) || _ <- lists:seq(1, Chunks)],
    TotalBytes = ?CHUNK_SIZE * Chunks,
    compare([hd(BinL) | BinL], TotalBytes).

compare(BinL, Bytes) ->
    {T1, _} = timer:tc(fun() -> match(BinL, Bytes, <<>>) end),
    {T2, _} = timer:tc(fun() -> sizer(BinL, Bytes, <<>>) end),
    io:format(user, "match: ~p\n"
                    "sizer: ~p\n", [T1, T2]).

match([Bin | Rest], N, Acc) ->
    case Acc of
        <<Head:N/binary, _/binary>> ->
            Head;
        _ ->
            match(Rest, N, <<Acc/binary, Bin/binary>>)
    end.

sizer([Bin | Rest], N, Acc) ->
    case size(Acc) >= N of
        true ->
            <<Head:N/binary, _/binary>> = Acc,
            Head;
        _ ->
            sizer(Rest, N, <<Acc/binary, Bin/binary>>)
    end.

Thank you @kjellwinblad